Lift Weights, Eat More Protein, Especially if You’re Over 40 Past studies have indicated that, in general, people will gain more strength and muscle mass while weight training if they up their intake of protein than if they do not. To answer the simplest question of whether taking in more protein during weight training led to larger increases in muscle size and strength, the researchers added all of the results together. Men and women who ate more protein while weight training did develop larger, stronger muscles than those who did not. So for the review, which was published in the British Journal of Sports Medicine, researchers from McMaster University in Hamilton, Ontario, and other institutions decided to aggregate the results from the best past studies of weight training and protein. People who would like to become physically stronger should start with weight training and add protein to their diets, according to a comprehensive scientific review of research. Whether everyone, including women, benefits similarly from consuming added protein while weight training and just how much protein is ideal, as well as what that protein should consist of and when it should be eaten, are all open questions. They wound up with 49 high-quality past experiments that had studied a total of 1,863 people, including men and women, young and old, and experienced weight trainers as well as novices. Almost everyone who started or continued weight training became stronger in these studies, whether they ate more protein or not.